[PATCH v2 1/2] dt-bindings: net: bluetooth: Add MediaTek MT7921S SDIO Bluetooth

From: Chen-Yu Tsai
Date: Fri Jan 26 2024 - 03:49:15 EST


The MediaTek MT7921S is a WiFi/Bluetooth combo chip that works over
SDIO. While the Bluetooth function is fully discoverable, the chip
has a pin that can reset just the Bluetooth side, as opposed to the
full chip. This needs to be described in the device tree.

Add a device tree binding for MT7921S Bluetooth over SDIO specifically
ot document the reset line.

Cc: Sean Wang <sean.wang@xxxxxxxxxxxx>
Signed-off-by: Chen-Yu Tsai <wenst@xxxxxxxxxxxx>
---
Changes since v1:
- Reworded descriptions
- Moved binding maintainer section before description
- Added missing reference to bluetooth-controller.yaml
- Added missing GPIO header to example

.../bluetooth/mediatek,mt7921s-bluetooth.yaml | 53 +++++++++++++++++++
MAINTAINERS | 1 +
2 files changed, 54 insertions(+)
create mode 100644 Documentation/devicetree/bindings/net/bluetooth/mediatek,mt7921s-bluetooth.yaml

diff --git a/Documentation/devicetree/bindings/net/bluetooth/mediatek,mt7921s-bluetooth.yaml b/Documentation/devicetree/bindings/net/bluetooth/mediatek,mt7921s-bluetooth.yaml
new file mode 100644
index 000000000000..ff11c95c816c
--- /dev/null
+++ b/Documentation/devicetree/bindings/net/bluetooth/mediatek,mt7921s-bluetooth.yaml
@@ -0,0 +1,53 @@
+# SPDX-License-Identifier: (GPL-2.0 OR BSD-2-Clause)
+%YAML 1.2
+---
+$id: http://devicetree.org/schemas/net/bluetooth/mediatek,mt7921s-bluetooth.yaml#
+$schema: http://devicetree.org/meta-schemas/core.yaml#
+
+title: MediaTek MT7921S Bluetooth
+
+maintainers:
+ - Sean Wang <sean.wang@xxxxxxxxxxxx>
+
+description:
+ MT7921S is an SDIO-attached dual-radio WiFi+Bluetooth Combo chip; each
+ function is its own SDIO function on a shared SDIO interface. The chip
+ has two dedicated reset lines, one for each function core.
+ This binding only covers the Bluetooth part of the chip.
+
+allOf:
+ - $ref: bluetooth-controller.yaml#
+
+properties:
+ compatible:
+ enum:
+ - mediatek,mt7921s-bluetooth
+ reg:
+ const: 2
+
+ reset-gpios:
+ maxItems: 1
+ description:
+ An active-low reset line for the Bluetooth core; on typical M.2
+ key E modules this is the W_DISABLE2# pin.
+
+required:
+ - compatible
+ - reg
+
+additionalProperties: false
+
+examples:
+ - |
+ #include <dt-bindings/gpio/gpio.h>
+
+ mmc {
+ #address-cells = <1>;
+ #size-cells = <0>;
+
+ bluetooth@2 {
+ compatible = "mediatek,mt7921s-bluetooth";
+ reg = <2>;
+ reset-gpios = <&pio 8 GPIO_ACTIVE_LOW>;
+ };
+ };
diff --git a/MAINTAINERS b/MAINTAINERS
index b64a64ca7916..662957146852 100644
--- a/MAINTAINERS
+++ b/MAINTAINERS
@@ -13657,6 +13657,7 @@ M: Sean Wang <sean.wang@xxxxxxxxxxxx>
L: linux-bluetooth@xxxxxxxxxxxxxxx
L: linux-mediatek@xxxxxxxxxxxxxxxxxxx (moderated for non-subscribers)
S: Maintained
+F: Documentation/devicetree/bindings/net/bluetooth/mediatek,mt7921s-bluetooth.yaml
F: Documentation/devicetree/bindings/net/mediatek-bluetooth.txt
F: drivers/bluetooth/btmtkuart.c

--
2.43.0.429.g432eaa2c6b-goog